Interferon stabilization

Abstract

The loss of biological activity of interferons is prevented or reduced by the addition of soluble lanthanide or calcium salts.

It is claimed: 
     
       1. A composition of matter comprising a solution of an interferon and a soluble lanthanide or calcium salt as a stabilizing agent for the interferon, wherein the salt is present at a concentration of at least about 0.0005 M for lanthanide salts except for neodymium, at least about 0.00008 M for a neodymium salt, and at least about 0.5 M for a calcium salt. 
     
     
       2. A composition of matter comprising a solution of human fibroblast interferon and a soluble lanthanide or calcium salt as a stabilizing agent for the interferon, wherein the salt is present at a concentration of at least about 0.0005 M for lanthanide salts except for neodynium, at least about 0.00008 M for a neodynium salt, and at least about 0.5 M for a calcium salt. 
     
     
       3. The composition of claim 2 wherein the salt is lanthanum chloride. 
     
     
       4. The composition of claim 2 wherein the salt is cerium chloride. 
     
     
       5. The composition of claim 2 wherein the salt is neodymium chloride. 
     
     
       6. The composition of claim 2 wherein the salt is samarium chloride. 
     
     
       7. The composition of claim 2 wherein the salt is gadolinium chloride. 
     
     
       8. The composition of claim 2 wherein the salt is dysprosium chloride. 
     
     
       9. The composition of claim 2 wherein the salt is erbium chloride. 
     
     
       10. The composition of claim 2 wherein the salt is ytterbium chloride. 
     
     
       11. The composition of claim 2 wherein the salt is lanthanum acetate. 
     
     
       12. The composition of claim 2 wherein the salt is calcium chloride. 
     
     
       13. The composition of claim 2 wherein the salt is calcium acetate. 
     
     
       14. A composition of matter comprising a solution of a human leukocyte interferon and a soluble lanthanide or calcium salt as a stabilizing agent for the interferon, wherein the salt is present at a concentration of at least about 0.0005 M for lanthanide salts except for neodymium, at least about 0.00008 M for a neodymium salt, and at least about 0.5 M for a calcium salt. 
     
     
       15. The composition of claim 14 wherein the salt is lanthanum chloride. 
     
     
       16. The composition of claim 14 wherein the salt is gadolinium chloride. 
     
     
       17. The composition of claim 14 wherein the salt is ytterbium chloride. 
     
     
       18. The composition of claim 14 wherein the salt is neodymium chloride. 
     
     
       19. The composition of claim 14 wherein the salt is calcium chloride. 
     
     
       20. A composition of matter comprising a solution of a mouse interferon and a soluble lanthanide or calcium salt as a stabilizing agent for the interferon, wherein the salt is present at a concentration of at least about 0.0005 M for lanthanide salts except for neodymium, at least about 0.00008 M for a neodymium salt, and at least about 0.5 M for a calcium salt. 
     
     
       21. The composition of claim 20 wherein the salt is calcium chloride. 
     
     
       22. A method for stabilizing interferon in solution comprising adding a soluble lanthanide or calcium salt to the interferon in solution, wherein the salt is present at a concentration of at least about 0.0005 M for lanthanide salts except for neodymium, at least about 0.00008 M for a neodymium salt, and at least about 0.5 M for a calcium salt, and adding a buffer to said solution and maintaining a pH such as will retain the lanthanide or calcium salt in solution.